4 Scatter Diagrams and Correlation Flashcards
association
when there is a relationship between 2 variables
when are scatter d’s good
bivariate data
correlation
association between 2 variables showing an increasing or decreasing trend
causal relationship
when change in one var. directly causes change in another var.
not necessarily implied by correlation
why is correlation != causation
how to draw line of best fit
plot through mean point
draw so the point are evenly spaced either side of it
interpolation vs extrapolation
interpolation: inside range
extrapolation: outside the range
interpolation more accurate, the further you extrapolate the less accurate it is
regression line
line of best fit
calculate constants of line of best fit
what are the constants of line of best fit
interpreting Spearman’s
interpreting PMCC
what does PMCC measure
strength of linear correlation between 2 data sets
